IDO1 and infection: This indicates that the recognition of EBER by RIG-I/IL-6/TNF-a is important for IDO expression and, therefore, contributes to an immunosuppressive setting; at the same time, the usual downstream pathway of RIG-I, particularly the IFN production, which is known as a potent antiviral, is affected by several other viral proteins and RNAs at some point during infection.